第三章 动词时态
时态问题怎么理解？
简单式
完成式
以简制繁的办法是：把be 动词当作动词，其后的分词则视为形容词补语。* 如果把be 动词抽离出来当作动词看待，那就只剩下用be 动词写的简单式，以及用have been 写的完成式两种状态。
分词可视为形容词补语，不放在动词短语里面
结语
- 把be动词当作动词看，句子就剩下两种时态，简单式与完成式
- 简单式是以括弧型的时间来表达
- 完成式是以箭头型的时间来表达
- be 动词后面的分词当作形容词补语，现在分词有正在进行的意思，过去分词有被动的意思。
- E.g.So far we have heard nothing from him.
- At present a new road is being built in that part of the city.
- Our city has changed a great deal. It doesn't resemble the one of three years ago.
- When Anna phoned me I had just finished my work and was starting to take a bath.
- There have been some very bad storms recently.
- The future price of this stock will be determined by serveal factory.
- The camera was invented in the 19th century. At that time, most photographers were professionals.
- The whole area was flooded because it has rained for weeks.
- By next Sunday you will have stayed with us for three months.
- We could smell that some one had been smoking
